Divergência genética entre acessos de feijão guadu no Cariri Paraibano.

Abstract

The Cajanus cajan, popularly known as pigeonpea was introduced in Brazil since the slavery times, utilized as green manure, human alimentation and animal alimentation. Being from Fabaceae family, subfamily Faboideae, is considered a shrub legume, or semi-perennial. Was aiming to its importance for the tropics and subtropics that in the current project aimed objective of this study was to carcaterize and verity the existence of genetic diversity among pigeonpea (Cajanus cajan) basead on quantitative and qualitative descriptors in a germoplasm bank formed by accessions collected in the Cariri region in Paraiba state. All 22 accessions of the pigeonpea germplasm bank were evaluated the completely randomized design (CRD) with the plot consisting of one plant per pot. It was also performed for these characters, the grouping test of means, according to Scott Knott proposed in 1974, to 5% of probabilty. The clustering method by the mean link between groups (UPGMA) was applied using the generalized mahalanobis distance (D2) (quantitative characters) and the average Euclidean distance (qualitative characters), as a measure of dissimilarity. The relative importance of the evaluated characters regarding the genetic dissimilarity observed between the genotypes was realized following the methodology employed by Morais and collaborators in 1998 and through the participation of D2 components, related to each trait, in the total dissimilarity observed. There is a wide genetic variability among the guandu bean accessions, and easily identified by morphoagronomic characters. G-LI/10-F18 and G-CON/11-F18 accessions are very likely to be duplicated, which should be molecularly confirmed. Seed-related characters allow easy identification of morphological genetic diversity. Nine intersections were identified as the most promising, namely: G-CA/18-M18 x (G-SU/02-J18, G-ZA/05-J18, GOV/22-M18, G-MO/04 -J18, G-PA/16-M18 and G-SJ/09-F18); G-PA/16-M18 x (G-SJ/09F18 and G-AM/19-M18) and the intersection between access G-SB/14-F18 and G-AM/19-M18.